Members of the People Power Party (PPP) have voted down a motion to replace the party's presidential candidate, Kim Moon-soo, with former Prime Minister Han Duck-soo.

The party on Saturday conducted an all-party vote through an automated phone survey to determine whether to replace Kim with Han but failed to secure majority approval.

Announcing the vote results on Saturday night, the party's interim leader, Kwon Young-se, offered to resign, apologizing for the chaos he had caused to party members and the public.

The vote followed an unprecedented move by the conservative party's leadership in the early hours of Saturday to nullify its primary, cancel Kim's nomination and register Han as both a party member and its new presidential candidate.

With the vote results, Kim was immediately reinstated as the conservative party's presidential candidate for the June 3 election.